Bor

5
B
Gruppe
13
Periode
2
Blok
p
Protons
Electrons
Neutrons
5
5
6
General Properties
Atomnummer
5
Atommasse
10,811
Mass Number
11
Kategori
Halvmetaller
Farve
Sort
Radioactive
Nej
From the Arabic word Buraq, Persian Burah
Krystalstruktur
Simpel Trigonal
History
Boron compounds have been known for thousands of years, but the element was not discovered until 1808 by Sir Humphry Davy and by Gay-Lussac and Thenard.

Boron was not recognized as an element until it was isolated in 1808 by Sir Humphry Davy and by Joseph Louis Gay-Lussac and Louis Jacques Thénard.

Jöns Jakob Berzelius identified boron as an element in 1824.
Elektroner i hver skal
2, 3
Elektronkonfiguration
[He] 2s2 2p1
B
Boron is an essential nutrient for all green plants
Physical Properties
Tilstandsform
Fast stof
Massefylde
2,34 g/cm3
Smeltepunkt
2349,15 K | 2076 °C | 3768,8 °F
Kogepunkt
4200,15 K | 3927 °C | 7100,6 °F
Smeltevarme
50 kJ/mol
Fordampningsvarme
507 kJ/mol
Varmefylde
1,026 J/g·K
Abundance in Earth's crust
0,00086%
Abundance in Universe
1×10-7%
Pure
Billede akkrediteringer: Images-of-elements
Pure crystalline boron, front side
CAS Number
7440-42-8
PubChem CID Number
5462311
Atomic Properties
Atomradius
90 pm
Kovalent radius
84 pm
Elektronegativitet
2,04 (Paulings skala)
Ionization Potential
8,298 eV
Atomic Volume
4,6 cm3/mol
Varmeledningsevne
0,274 W/cm·K
Oxidationstrin
1, 2, 3
Applications
Boron oxide is used in glassmaking and ceramics.

Borax is used in making fiberglass, as a cleansing fluid, a water softener, insecticide, herbicide and disinfectant.

Boric acid is used as a mild antiseptic and as a flame retardant.

Boron shielding is used as a control for nuclear reactors.
Elemental boron, boron oxide, boric acid, borates and many organoboron compounds are non-toxic
Isotoper
Stable Isotopes
10B, 11B
Unstable Isotopes
7B, 8B, 9B, 12B, 13B, 14B, 15B, 16B, 17B, 18B, 19B